A1C ≥6.5%. The test should be performed in a laboratory using a method that is National Glycohemoglobin Standardization Program (NGSP)-certified and standardized to the Diabetes Control and Complications Trial (DCCT) assay

fasting plasma glucose (FPG) ≥126 mg/dl (7.0 mmol/l). Fasting is defined as no caloric intake for at least 8 h, or

2-h plasma glucose ≥200 mg/dl (11.1 mmol/l) during an oral glucose tolerance test (OGTT). The test should be performed as described by the World Health Organization, using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water

in a patient with classic symptoms of hyperglycemia or hyperglycemic crisis, a random plasma glucose ≥200 mg/dl (11.1 mmol/l)

in the absence of unequivocal hyperglycemia, result should be confirmed by repeat testing.

Testing to detect type 2 diabetes and assess risk for future diabetes in asymptomatic people should be considered in adults of any age who are overweight or obese (BMI ≥25 kg/m²) and who have one or more additional risk factors for diabetes (see Table 4 of the “Standards of Medical Care in Diabetes—2011”). In those without these risk factors, testing should begin at age 45 years. (B)

If tests are normal, repeat testing carried out at least at 3-year intervals is reasonable. (E)

To test for diabetes or to assess risk of future diabetes, A1C, FPG, or 2-h 75-g OGTT are appropriate. (B)

In those identified with increased risk for future diabetes, identify and, if appropriate, treat other cardiovascular disease (CVD) risk factors. (B)

Screen for undiagnosed type 2 diabetes at the first prenatal visit in those with risk factors, using standard diagnostic criteria. (B)

In pregnant women not known to have diabetes, screen for GDM at 24–28 weeks of gestation, using a 75-g 2-h OGTT and the diagnostic cut points in Table 6 …